HD6413008VF25 Datasheet, PDF (634/688 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Appendix B Internal I/O Registers
SSR—Serial Status Register
H'FFFB4
SCI0
Bit
Initial value
Read/Write
7
TDRE
1
R/(W)*
6
RDRF
0
R/(W)*
5
4
3
ORER
0
R/(W)*
FER/ERS
0
R/(W)*
PER
0
R/(W)*
2
TEND
1
R
1
MPB
0
R
0
MPBT
0
R/W
Multiprocessor bit transfer
0 Multiprocessor bit value in transmit data is 0
1 Multiprocessor bit value in transmit data is 1
Multiprocessor bit
0 Multiprocessor bit value in receive data is 0
1 Multiprocessor bit value in receive data is 1
Transmit end (for serial communication interface)
0
[Clearing condition]
Read TDRE when TDRE = 1, then write 0 in TDRE.
[Setting conditions]
• Reset or transition to standby mode
1 ^{• TE is cleared to 0 in SCR.}
• TDRE is 1 when last bit of 1-byte serial character is
transmitted.
Transmit end (for smart card interface)
[Clearing condition]
0 _{Read TDRE when TDRE = 1, then write 0 in TDRE.}
[Setting conditions]
• Reset or transition to standby mode
1 ^{• TE is cleared to 0 in SCR and FER/ERS is cleared to 0.}
• TDRE is 1 and FER/ERS is 0 (normal transmission)
2.5 etu* (when GM = 0) or 1.0 etu (when GM = 1) after
1-byte serial character is transmitted.
Note: * etu: Elementary time unit (time required to transmit one bit)
Parity error
0
[Clearing conditions] • Reset or transition to standby mode
• Read PER when PER = 1, then write 0 in PER.
1 ^{[Setting condition]}
Parity error (parity of receive data does not match parity
setting of O/E bit in SMR)
Framing error (for serial communication interface)
0
[Clearing conditions]
• Reset or transition to standby mode
• Read FER when FER = 1, then write 0 in FER.
1 [Setting condition] Framing error (stop bit is 0)
Error signal status (for smart card interface)
0
[Clearing conditions]
• Reset or transition to standby mode
• Read ERS when ERS = 1, then write 0 in ERS.
1 [Setting condition] A low error signal is received.
Overrun error
0
[Clearing conditions]
• Reset or transition to standby mode
• Read ORER when ORER = 1, then write 0 in ORER.
1 [Setting condition] Overrun error (reception of the next serial data ends when RDRF = 1)
Receive data register full
0
[Clearing conditions]
• Reset or transition to standby mode
• Read RDRF when RDRF = 1, then write 0 in RDRF.
1 [Setting condition] Serial data is received normally and transferred from RSR to RDR.
Transmit data register empty
0 [Clearing condition] Read TDRE when TDRE = 1, then write 0 in TDRE.
[Setting conditions]
1
• Reset or transition to standby mode
• TE is 0 in SCR.
• Data is transferred from TDR to TSR, enabling new data to be written in TDR
Note: * Only 0 can be written, to clear the flag.
Rev.4.00 Aug. 20, 2007 Page 588 of 638
REJ09B0395-0400